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Food Additives & Contaminants: Part B: Surveillance Publication details, including instructions for authors and subscription information: http://www.tandfonline.com/loi/tfab20
Evaluation of heavy metals contamination in Iranian foodstuffs: canned tomato paste and tomato sauce (ketchup) a
b
c
d
Mohammad Rasoul Hadiani , Roqieh Farhangi , Homeira Soleimani , Hossein Rastegar & Abdol Majid Cheraghali
b
a
Heavy Metals Analysis Laboratory, Food and Drug Laboratory Research Center, Food and Drug Organization, Tehran, Iran b
Department of Toxicology and Pharmacology and Chemical Injuries, University of Baqiyatallah Medical Sciences, Tehran, Iran c
Department of Biology, Shahr-Qods Branch, Islamic Azad University, Tehran, Iran
d
Food and Drug Reference Laboratories Center, Food and Drug Organization, Tehran, Iran Accepted author version posted online: 25 Sep 2013.Published online: 21 Nov 2013.
To cite this article: Mohammad Rasoul Hadiani, Roqieh Farhangi, Homeira Soleimani, Hossein Rastegar & Abdol Majid Cheraghali (2014) Evaluation of heavy metals contamination in Iranian foodstuffs: canned tomato paste and tomato sauce (ketchup), Food Additives & Contaminants: Part B: Surveillance, 7:1, 74-78, DOI: 10.1080/19393210.2013.848384 To link to this article: http://dx.doi.org/10.1080/19393210.2013.848384
PLEASE SCROLL DOWN FOR ARTICLE Taylor & Francis makes every effort to ensure the accuracy of all the information (the “Content”) contained in the publications on our platform. However, Taylor & Francis, our agents, and our licensors make no representations or warranties whatsoever as to the accuracy, completeness, or suitability for any purpose of the Content. Any opinions and views expressed in this publication are the opinions and views of the authors, and are not the views of or endorsed by Taylor & Francis. The accuracy of the Content should not be relied upon and should be independently verified with primary sources of information. Taylor and Francis shall not be liable for any losses, actions, claims, proceedings, demands, costs, expenses, damages, and other liabilities whatsoever or howsoever caused arising directly or indirectly in connection with, in relation to or arising out of the use of the Content. This article may be used for research, teaching, and private study purposes. Any substantial or systematic reproduction, redistribution, reselling, loan, sub-licensing, systematic supply, or distribution in any form to anyone is expressly forbidden. Terms & Conditions of access and use can be found at http:// www.tandfonline.com/page/terms-and-conditions
Food Additives & Contaminants: Part B, 2014 Vol. 7, No. 1, 74–78, http://dx.doi.org/10.1080/19393210.2013.848384
Evaluation of heavy metals contamination in Iranian foodstuffs: canned tomato paste and tomato sauce (ketchup) Mohammad Rasoul Hadiania*, Roqieh Farhangib, Homeira Soleimanic, Hossein Rastegard and Abdol Majid Cheraghalib a
Heavy Metals Analysis Laboratory, Food and Drug Laboratory Research Center, Food and Drug Organization, Tehran, Iran; Department of Toxicology and Pharmacology and Chemical Injuries, University of Baqiyatallah Medical Sciences, Tehran, Iran; c Department of Biology, Shahr-Qods Branch, Islamic Azad University, Tehran, Iran; dFood and Drug Reference Laboratories Center, Food and Drug Organization, Tehran, Iran b
Downloaded by [Northeastern University] at 02:56 24 November 2014
(Received 15 July 2013; accepted 21 September 2013) One hundred and thirty-five samples of canned tomato paste and 30 tomato sauces (ketchup) samples (23 and 10 brands, respectively) purchased from wholesale markets in the Tehran, Iran, during the period 2010–2013 were analysed. Levels of lead and cadmium were determined by graphite furnace atomic absorption spectrophotometer (GF-AAS) and arsenic by hydride vapour generation (HG-AAS or VGA). Average concentration of arsenic found in the tomato paste and ketchup samples was 62 ± 14 and 48 ± 12 ng g−1, respectively. Cadmium values in 7% of tomato paste and 10% of ketchup samples were below the limit of quantification (LOQ). Lead concentrations were below LOQ in 75% of tomato paste and 77% of ketchup samples. Values obtained for these heavy metals in all samples were lower than the limits of national and international standards. Keywords: tomato paste; ketchup; lead; cadmium; arsenic; microwave digestion; heavy metals
Introduction Due to its principal carotenoid lycopene content, tomato (Lycopersicone esculentum) is an important antioxidant source which may prevent cancer especially prostate cancer (Bhuvaneswari & Nagini 2005; Ilic et al. 2011), as well as decrease the risk of stroke in men (Karppi et al. 2012). Two important tomato products are tomato paste and tomato sauce (ketchup), which are frequently consumed in the Iranian diet, affording favourite taste and colour in food. However, these products may contain some contaminants among heavy metals through uptake by plants from contaminated soil, water or applied agrochemicals. Also, processing and canning or leaching from the metal cans during storage may insert heavy metals into tomato paste or sauce (Nincević et al. 2009). Addition of stabilisers, preservatives and synthetic colouring agents are other ways for heavy metal contamination in tomato products (Oduoza 1992). Due to their widespread occurrence, toxicity and cumulative behaviour, heavy metals can be considered as a potential hazardous threat to human health and crop plants (Shi & Cai 2009). Furthermore, the consumption of heavy metal-contaminated food can seriously deplete some essential nutrients in the body causing a decrease in immunological defences, intrauterine growth retardation, impaired psycho-social behaviour, disabilities associated with malnutrition and a high prevalence of upper gastrointestinal cancer (Arora et al. 2008). On the other hand, tending of these elements to persist and bio-accumulate in *Corresponding author. Email: [email protected] © 2013 Taylor & Francis
bio-organisms can enhance their concentrations in target tissues and organs (Nishihara et al. 1985). Although in-house and industrial consumption of tomato paste and ketchup is very high in Iran, there are very few studies about them (Poormoghaddas et al. 2002). Therefore this study was performed to increase available data of lead (Pb) and cadmium (Cd) contamination as well as a survey of arsenic in tomato paste and ketchup produced in Iran during a 3.5-year period. Sample preparation method was microwave digestion and measurement methods were graphite furnace atomic absorption spectrophotometer (GF-AAS) and hydride vapour generation (HG-AAS or VGA). Materials and methods Sampling Samples of 0.5 and 1 kg canned tomato paste (n = 135) and 0.3 and 0.5 kg tomato sauce with plastic packaging (n = 30) from 23 and 10 different brands, respectively, were purchased from major wholesale markets in Tehran areas during the period 2010–2012 and the first half of 2013. All samples were obtained from different production series covering all prevalent brands consumed in Tehran. Samples were transported to the Heavy Metals lab of the Food and Drug Organization. After opening the packages, their content was transferred into clean plastic bags, coded as brand and production serial and then frozen at –20°C until analysis.
Food Additives & Contaminants: Part B
Downloaded by [Northeastern University] at 02:56 24 November 2014
Reagents and solutions Analytical reagent-grade chemicals from Merck (Darmstadt, Germany) and deionised water with resistivity 18.0 MΩ cm (Elga Labwater, Wycombe Bucks, UK) were used for preparation of all solutions and sample dilution. Standard solutions of lead and cadmium (1000 mg l−1 solutions in 0.1 M HNO3) were provided by Panreac (Panreac Quimica SA, Barcelona, Spain). Working standard solutions were freshly prepared in a HNO3–H2O2 solution (5:2), similar to microwave sample extracts. For arsenic calibration, an Aldrich 1000 mg l−1 standard stock solution was used (Sigma Aldrich, St. Louis, MO, USA). Its working standard solutions were prepared in 10% (v/v) HCl. CS-M-2 (dried mushroom powder) certified reference material was obtained from the Institute of Nuclear Chemistry & Technology (Warsaw, Poland) and NCSZC73008 (rice) and NCSZC73015 (milk powder) certified reference materials were obtained from the China National Analysis Center for Iron and Steel (Beijing, China). All plastic, glassware and Teflon beakers were cleaned and soaked in 10% (v/v) HNO3 overnight and rinsed with deionised water prior to analysis. Apparatus A Varian Spectra AA-240FS atomic absorption spectrometer (Varian Australia, Pty Ltd, Mulgrave, Victoria) equipped with a GTA-120 graphite furnace atomiser and deuterium lamp as a background corrector was used in the experiments. For lead and cadmium, a Varian programmable sample dispenser (PSD120) was employed for injecting sample solutions along with orthophosphoric acid solution (1000 mg l−1) as modifier into the furnace. All experiments were performed using pyrolytic-coated partitioned graphite tubes. The signals were measured as peak height. The operating parameters for lead and cadmium were set as recommended by the manufacturer (Table 1). For arsenic determination, a VGA-77 hydride vapour generation system (Varian Australia, Pty Ltd, Mulgrave, Victoria, Australia) with air/acetylene flame was used. All samples were injected in triplicate. A Speed Wave 4 microwave system (Berghof Products + Instruments GmbH, Eningen, Germany), maximum pressure 40 bar and maximum temperature 230°C Table 1. Operating parameters for the measurement of lead, cadmium and arsenic in tomato paste and ketchup samples. Parameters
Lead
Cadmium
Arsenic
Lamp current (mA) Wavelength (nm) Slit width (nm) Sample volume (µl) Modifier volume (µl)
10 283.3 0.5 20 5
6 228.8 0.5 15 5
6 193.7 0.5 – –
75
with Teflon reaction vessels, was applied for all digestions. Sample preparation Each 1 kg canned tomato paste or tomato sauce sample was thoroughly transferred to a mixer and homogenised. Then, 1 g was accurately weighed and processed with a mixture of 5 ml of nitric acid and 2 ml of hydrogen peroxide in the microwave digestion system. The tomato paste and sauce samples were digested according the following programme: step 1 (T, 160°C; ramp, 15 min; time, 10 min), step 2 (T, 175°C; ramp, 15 min; time, 5 min). For the certified reference material preparation, an amount of approximately 0.5 g of sample (CS-M-2 mushroom powder, NCSZC73008 rice and NCSZC73015 milk powder) was digested as described for samples. After digestion, the volume of resulting extract was measured and 1 ml was removed for subsequent analysis of lead and cadmium by GF-AAS. The remaining extract was used for arsenic determination according to Mindak and Dolan (1999). Briefly, the microwave extract was transferred to a glass beaker containing 2 ml ashing aid (2% MgO suspension in 20% Mg (NO3)2.6H2O solution m/v) and carefully heated on a hotplate until dry. Beakers were placed in a muffle furnace and ashed. The ashes were dissolved by 4.5 ml of 6 M HCl and 2 ml 50% hydroxylamine hydrochloride and 0.4 ml KI/ascorbic acid solution were added. The dissolved ash solution was diluted to 10 ml and after waiting at least 1 h to ensure complete reduction of As5+ to As3+, arsenic analysis performed. Method validation The validity of the sample preparation procedure and instrumental parameters was determined by adding increasing amounts of lead, cadmium and arsenic within 3 days to blank samples which were then passing the extraction procedures. The results are reported in Table 2. Mean recoveries for lead, cadmium and arsenic were 94.5%, 87% and 104%, respectively, with coefficients of variation of 6.5%, 5% and 8%, respectively. These values demonstrated the accuracy of the methods used. The limits of detection (LODs), defined as the concentration of each element corresponding to 3 times the standard deviation of 10 reagent blanks, were 1, 0.2 and 1 ng g−1 for Pb, Cd and As, respectively. The limits of quantification (LOQs), defined as the concentration of each element corresponding to 10 times the standard deviation of 10 reagent blanks, were 3, 0.6 and 3 ng g−1 for Pb, Cd and As, respectively. Moreover, the validity of the used methods was evaluated by analysing three certified reference samples:
76
M.R. Hadiani et al.
Table 2. Recoveries of lead, cadmium and arsenic in tomato paste and ketchup samples within 3 days. Concentration\element Spike level (ng g−1) Mean result (ng g−1) Mean recovery (%)
Pb 25 23 92
50 49 98
Cd 100 97 97
200 183 91
25 21 84
mushroom powder (CS-M-2), rice (NCSZC73008) and milk powder (NCSZC73015). From Table 3, it can be concluded that these data show good agreement.
Downloaded by [Northeastern University] at 02:56 24 November 2014
Results and discussion The concentrations of lead, cadmium and arsenic in different brands of canned tomato paste and tomato sauce are presented in Table 4. Levels of lead concentration in 102 (75%) tomato paste and 23 (77%) ketchup samples were lower than LOQ (
Food Additives & Contaminants: Part B: Surveillance Publication details, including instructions for authors and subscription information: http://www.tandfonline.com/loi/tfab20
Evaluation of heavy metals contamination in Iranian foodstuffs: canned tomato paste and tomato sauce (ketchup) a
b
c
d
Mohammad Rasoul Hadiani , Roqieh Farhangi , Homeira Soleimani , Hossein Rastegar & Abdol Majid Cheraghali
b
a
Heavy Metals Analysis Laboratory, Food and Drug Laboratory Research Center, Food and Drug Organization, Tehran, Iran b
Department of Toxicology and Pharmacology and Chemical Injuries, University of Baqiyatallah Medical Sciences, Tehran, Iran c
Department of Biology, Shahr-Qods Branch, Islamic Azad University, Tehran, Iran
d
Food and Drug Reference Laboratories Center, Food and Drug Organization, Tehran, Iran Accepted author version posted online: 25 Sep 2013.Published online: 21 Nov 2013.
To cite this article: Mohammad Rasoul Hadiani, Roqieh Farhangi, Homeira Soleimani, Hossein Rastegar & Abdol Majid Cheraghali (2014) Evaluation of heavy metals contamination in Iranian foodstuffs: canned tomato paste and tomato sauce (ketchup), Food Additives & Contaminants: Part B: Surveillance, 7:1, 74-78, DOI: 10.1080/19393210.2013.848384 To link to this article: http://dx.doi.org/10.1080/19393210.2013.848384
PLEASE SCROLL DOWN FOR ARTICLE Taylor & Francis makes every effort to ensure the accuracy of all the information (the “Content”) contained in the publications on our platform. However, Taylor & Francis, our agents, and our licensors make no representations or warranties whatsoever as to the accuracy, completeness, or suitability for any purpose of the Content. Any opinions and views expressed in this publication are the opinions and views of the authors, and are not the views of or endorsed by Taylor & Francis. The accuracy of the Content should not be relied upon and should be independently verified with primary sources of information. Taylor and Francis shall not be liable for any losses, actions, claims, proceedings, demands, costs, expenses, damages, and other liabilities whatsoever or howsoever caused arising directly or indirectly in connection with, in relation to or arising out of the use of the Content. This article may be used for research, teaching, and private study purposes. Any substantial or systematic reproduction, redistribution, reselling, loan, sub-licensing, systematic supply, or distribution in any form to anyone is expressly forbidden. Terms & Conditions of access and use can be found at http:// www.tandfonline.com/page/terms-and-conditions
Food Additives & Contaminants: Part B, 2014 Vol. 7, No. 1, 74–78, http://dx.doi.org/10.1080/19393210.2013.848384
Evaluation of heavy metals contamination in Iranian foodstuffs: canned tomato paste and tomato sauce (ketchup) Mohammad Rasoul Hadiania*, Roqieh Farhangib, Homeira Soleimanic, Hossein Rastegard and Abdol Majid Cheraghalib a
Heavy Metals Analysis Laboratory, Food and Drug Laboratory Research Center, Food and Drug Organization, Tehran, Iran; Department of Toxicology and Pharmacology and Chemical Injuries, University of Baqiyatallah Medical Sciences, Tehran, Iran; c Department of Biology, Shahr-Qods Branch, Islamic Azad University, Tehran, Iran; dFood and Drug Reference Laboratories Center, Food and Drug Organization, Tehran, Iran b
Downloaded by [Northeastern University] at 02:56 24 November 2014
(Received 15 July 2013; accepted 21 September 2013) One hundred and thirty-five samples of canned tomato paste and 30 tomato sauces (ketchup) samples (23 and 10 brands, respectively) purchased from wholesale markets in the Tehran, Iran, during the period 2010–2013 were analysed. Levels of lead and cadmium were determined by graphite furnace atomic absorption spectrophotometer (GF-AAS) and arsenic by hydride vapour generation (HG-AAS or VGA). Average concentration of arsenic found in the tomato paste and ketchup samples was 62 ± 14 and 48 ± 12 ng g−1, respectively. Cadmium values in 7% of tomato paste and 10% of ketchup samples were below the limit of quantification (LOQ). Lead concentrations were below LOQ in 75% of tomato paste and 77% of ketchup samples. Values obtained for these heavy metals in all samples were lower than the limits of national and international standards. Keywords: tomato paste; ketchup; lead; cadmium; arsenic; microwave digestion; heavy metals
Introduction Due to its principal carotenoid lycopene content, tomato (Lycopersicone esculentum) is an important antioxidant source which may prevent cancer especially prostate cancer (Bhuvaneswari & Nagini 2005; Ilic et al. 2011), as well as decrease the risk of stroke in men (Karppi et al. 2012). Two important tomato products are tomato paste and tomato sauce (ketchup), which are frequently consumed in the Iranian diet, affording favourite taste and colour in food. However, these products may contain some contaminants among heavy metals through uptake by plants from contaminated soil, water or applied agrochemicals. Also, processing and canning or leaching from the metal cans during storage may insert heavy metals into tomato paste or sauce (Nincević et al. 2009). Addition of stabilisers, preservatives and synthetic colouring agents are other ways for heavy metal contamination in tomato products (Oduoza 1992). Due to their widespread occurrence, toxicity and cumulative behaviour, heavy metals can be considered as a potential hazardous threat to human health and crop plants (Shi & Cai 2009). Furthermore, the consumption of heavy metal-contaminated food can seriously deplete some essential nutrients in the body causing a decrease in immunological defences, intrauterine growth retardation, impaired psycho-social behaviour, disabilities associated with malnutrition and a high prevalence of upper gastrointestinal cancer (Arora et al. 2008). On the other hand, tending of these elements to persist and bio-accumulate in *Corresponding author. Email: [email protected] © 2013 Taylor & Francis
bio-organisms can enhance their concentrations in target tissues and organs (Nishihara et al. 1985). Although in-house and industrial consumption of tomato paste and ketchup is very high in Iran, there are very few studies about them (Poormoghaddas et al. 2002). Therefore this study was performed to increase available data of lead (Pb) and cadmium (Cd) contamination as well as a survey of arsenic in tomato paste and ketchup produced in Iran during a 3.5-year period. Sample preparation method was microwave digestion and measurement methods were graphite furnace atomic absorption spectrophotometer (GF-AAS) and hydride vapour generation (HG-AAS or VGA). Materials and methods Sampling Samples of 0.5 and 1 kg canned tomato paste (n = 135) and 0.3 and 0.5 kg tomato sauce with plastic packaging (n = 30) from 23 and 10 different brands, respectively, were purchased from major wholesale markets in Tehran areas during the period 2010–2012 and the first half of 2013. All samples were obtained from different production series covering all prevalent brands consumed in Tehran. Samples were transported to the Heavy Metals lab of the Food and Drug Organization. After opening the packages, their content was transferred into clean plastic bags, coded as brand and production serial and then frozen at –20°C until analysis.
Food Additives & Contaminants: Part B
Downloaded by [Northeastern University] at 02:56 24 November 2014
Reagents and solutions Analytical reagent-grade chemicals from Merck (Darmstadt, Germany) and deionised water with resistivity 18.0 MΩ cm (Elga Labwater, Wycombe Bucks, UK) were used for preparation of all solutions and sample dilution. Standard solutions of lead and cadmium (1000 mg l−1 solutions in 0.1 M HNO3) were provided by Panreac (Panreac Quimica SA, Barcelona, Spain). Working standard solutions were freshly prepared in a HNO3–H2O2 solution (5:2), similar to microwave sample extracts. For arsenic calibration, an Aldrich 1000 mg l−1 standard stock solution was used (Sigma Aldrich, St. Louis, MO, USA). Its working standard solutions were prepared in 10% (v/v) HCl. CS-M-2 (dried mushroom powder) certified reference material was obtained from the Institute of Nuclear Chemistry & Technology (Warsaw, Poland) and NCSZC73008 (rice) and NCSZC73015 (milk powder) certified reference materials were obtained from the China National Analysis Center for Iron and Steel (Beijing, China). All plastic, glassware and Teflon beakers were cleaned and soaked in 10% (v/v) HNO3 overnight and rinsed with deionised water prior to analysis. Apparatus A Varian Spectra AA-240FS atomic absorption spectrometer (Varian Australia, Pty Ltd, Mulgrave, Victoria) equipped with a GTA-120 graphite furnace atomiser and deuterium lamp as a background corrector was used in the experiments. For lead and cadmium, a Varian programmable sample dispenser (PSD120) was employed for injecting sample solutions along with orthophosphoric acid solution (1000 mg l−1) as modifier into the furnace. All experiments were performed using pyrolytic-coated partitioned graphite tubes. The signals were measured as peak height. The operating parameters for lead and cadmium were set as recommended by the manufacturer (Table 1). For arsenic determination, a VGA-77 hydride vapour generation system (Varian Australia, Pty Ltd, Mulgrave, Victoria, Australia) with air/acetylene flame was used. All samples were injected in triplicate. A Speed Wave 4 microwave system (Berghof Products + Instruments GmbH, Eningen, Germany), maximum pressure 40 bar and maximum temperature 230°C Table 1. Operating parameters for the measurement of lead, cadmium and arsenic in tomato paste and ketchup samples. Parameters
Lead
Cadmium
Arsenic
Lamp current (mA) Wavelength (nm) Slit width (nm) Sample volume (µl) Modifier volume (µl)
10 283.3 0.5 20 5
6 228.8 0.5 15 5
6 193.7 0.5 – –
75
with Teflon reaction vessels, was applied for all digestions. Sample preparation Each 1 kg canned tomato paste or tomato sauce sample was thoroughly transferred to a mixer and homogenised. Then, 1 g was accurately weighed and processed with a mixture of 5 ml of nitric acid and 2 ml of hydrogen peroxide in the microwave digestion system. The tomato paste and sauce samples were digested according the following programme: step 1 (T, 160°C; ramp, 15 min; time, 10 min), step 2 (T, 175°C; ramp, 15 min; time, 5 min). For the certified reference material preparation, an amount of approximately 0.5 g of sample (CS-M-2 mushroom powder, NCSZC73008 rice and NCSZC73015 milk powder) was digested as described for samples. After digestion, the volume of resulting extract was measured and 1 ml was removed for subsequent analysis of lead and cadmium by GF-AAS. The remaining extract was used for arsenic determination according to Mindak and Dolan (1999). Briefly, the microwave extract was transferred to a glass beaker containing 2 ml ashing aid (2% MgO suspension in 20% Mg (NO3)2.6H2O solution m/v) and carefully heated on a hotplate until dry. Beakers were placed in a muffle furnace and ashed. The ashes were dissolved by 4.5 ml of 6 M HCl and 2 ml 50% hydroxylamine hydrochloride and 0.4 ml KI/ascorbic acid solution were added. The dissolved ash solution was diluted to 10 ml and after waiting at least 1 h to ensure complete reduction of As5+ to As3+, arsenic analysis performed. Method validation The validity of the sample preparation procedure and instrumental parameters was determined by adding increasing amounts of lead, cadmium and arsenic within 3 days to blank samples which were then passing the extraction procedures. The results are reported in Table 2. Mean recoveries for lead, cadmium and arsenic were 94.5%, 87% and 104%, respectively, with coefficients of variation of 6.5%, 5% and 8%, respectively. These values demonstrated the accuracy of the methods used. The limits of detection (LODs), defined as the concentration of each element corresponding to 3 times the standard deviation of 10 reagent blanks, were 1, 0.2 and 1 ng g−1 for Pb, Cd and As, respectively. The limits of quantification (LOQs), defined as the concentration of each element corresponding to 10 times the standard deviation of 10 reagent blanks, were 3, 0.6 and 3 ng g−1 for Pb, Cd and As, respectively. Moreover, the validity of the used methods was evaluated by analysing three certified reference samples:
76
M.R. Hadiani et al.
Table 2. Recoveries of lead, cadmium and arsenic in tomato paste and ketchup samples within 3 days. Concentration\element Spike level (ng g−1) Mean result (ng g−1) Mean recovery (%)
Pb 25 23 92
50 49 98
Cd 100 97 97
200 183 91
25 21 84
mushroom powder (CS-M-2), rice (NCSZC73008) and milk powder (NCSZC73015). From Table 3, it can be concluded that these data show good agreement.
Downloaded by [Northeastern University] at 02:56 24 November 2014
Results and discussion The concentrations of lead, cadmium and arsenic in different brands of canned tomato paste and tomato sauce are presented in Table 4. Levels of lead concentration in 102 (75%) tomato paste and 23 (77%) ketchup samples were lower than LOQ (
